What they had actually recorded was a cashel, a type of ringfort defined by a drystone enclosing wall rather than an earthen bank, sitting quietly on a low rise in the middle of open, rolling pasture on the Longford Demesne. The fact that it could be mistaken for a woodland feature or a worked quarry says something about how thoroughly time and agricultural activity had softened its outline by the nineteenth century.

The structure is roughly oval, measuring about 37.6 metres east to west and 30.8 metres north to south. Its enclosing wall, now grass-covered and incorporated with heaps of field clearance stones gathered by farmers over generations, still survives to an internal height of between half a metre and a metre, and retains a width of between five and nearly six metres in places. Wide breaks in the wall at the northwest and southeast likely indicate original entrance points, though later disturbance cannot be ruled out. Just beyond the southeastern break lies evidence for a souterrain, an underground passage or chamber typically associated with early medieval ringforts and thought to have served for storage, refuge, or concealment. Adjoining the eastern side of the cashel is a separate rectangular enclosure, a feature that hints at a more complex arrangement of space than a simple farmstead enclosure would require, though its precise function is not recorded.